UC San Diego computer scientists have figured out how exactly Volkswagen cheated emissions tests. And they also found evidence that Volkswagen is not the only automaker deceiving regulators.
Kirill Levchenko, who led the research, said it took about a year to find the "smoking gun" software implicating Volkswagen.
"As technical people, we were curious. We wanted to find that one piece of code that's costing them $20 billion," Levchenko said.
The test-dodging software turned out to be hidden in a program labeled "acoustic condition," apparently meant to control engine noise.
RELATED: Lawsuit Claims GM Used Defeat Devices On Duramax Diesel Trucks And SUVs
But Levchenko and his colleagues — including researchers at Ruhr University in Germany — found signs that this string of code was actually designed to determine whether the car was being driven normally or being put through a regulatory test, in which case its behavior would alter to limit emissions.
"It would assume that you are in a driving test," said Levchenko. But the moment drivers sped up, slowed down or turned the wheel in ways that suggested the car was not being tested, "It would disable this condition."
The researchers also found what appears to be much simpler deception software in the Fiat 500X, a diesel SUV sold in Europe. Levchenko said documentation of the vehicle's software revealed a timing program that instructed the car to limit emissions for the first 26 minutes or so of driving, about how long it takes to complete an emissions test.
"I came across this figure that showed these two different logic paths. One was labeled 'homologation' and the other 'real driving.' I didn't know what 'homologation' meant, but 'real driving' looked very suspicious," he said.
"Homologation" turns out to be a term that refers to the process officially approving something, as in a regulatory test. The car's emissions behaved very differently under this setting than it did under "real driving."
Fiat Chrysler is reportedly seeking a settlement with the U.S. Department of Justice over mounting evidence that it has been evading diesel emissions standards.
"As we went along, we realized that this is part of a much bigger problem," Levchenko said. "Regulators who are used to regulating a very simple mechanical device, like an old-style car, will now have to be regulating a software system."
The researchers presented their findings at a conference earlier this week.
